Machine for forming straws

ABSTRACT

A machine for folding straws to temporarily alter a straw&#39;&#39;s configuration, shorten it and form a liquid-tight seal in the straw. A rotating chuck folds the straw over anvil surfaces to form two crease lines in the straw. The chuck folds an upper straw section on these crease lines into perpendicular relationship with a lower straw section while forming a liquid tight seal at the folds.

United States Patent 1151 3,659,507 Cushman 51 May 2, 1972 s41 MACHINEFOR FORMING STRAWS 3,242,828 3/1966 Larkin..... ....93/94 R 3,290,19812/1966 Lux ....93/94 R [72] Inventor. Robert D. Cushman, FortLauderdale, Fla. 3,398,659 8/1968 Egleston "AB/84 Tw [73] Assignee:Jenos, Inc., Duluth, Minn. 3,452,516 7/1969 Smith ..93/84 TW 1 Fi1ed=271 FOREIGN PATENTS 0R APPLICATIONS 1211 PP 931082 1,246,318 10/1960 1France 229/7 5 717,909 11/1954 Great Britain ..93/84 TW 52 us. c1..93/84 Tw, 93/368, 93/94 R 8701551 6/1961 Great Britain -93/94 R [51]Int. Cl. ..B3ld 5/04,B3lc l1/02,B3lb45/00 [58] Field of Search ..99 171B; 229/7 5; 93/36 M, Prmwry E-wmmerwayne Morse- 93/3 3 4 TW' 94 RAttorney-Hume, Clement, Hume & Lee

[56] References Cited ABSTRACT UNITED STATES PATENTS A machine forfolding straws to temporarily alter a straws configuration, shorten Itand form a lIquId-tight seal in the 2,054,024 9/1936 Pye ..93/84 TW t Arotating huck folds the straw over anvil surfaces to 1 1 4/1948Bogoslowsky 93/36 8 form two crease lines in the straw. The chuck foldsan upper 314601939 2/1 949 1 R straw section on these crease lines intoperpendicular relation- 2-466183O 4/1949 Tofflemlre 93/84 Tw ship with alower straw section while forming a liquid tight seal 2,800,265 7/1957Pugh I ..229/7 S at the f ]d 2,901 ,357 8/1959 Epstein ..99/171 B3,122,297 2/1964 Sachs ..229/7 8 13 Claims, 9 Drawing Figures PatentedMay 2, 1972 3,659,507

2 Sheets-Sheet l Patented May 2, 1972 3,659,507

2 Sheets-Sheet 2.

alm Z 10km MACHINE FOR FORMING STRAWS BACKGROUND OF THE INVENTION Thisinvention relates in general to a machine for folding straws. It deals,more particularly, with a machine for folding straws to temporarilyalter a straws configuration, shorten it and form a liquid-tight seal inthe straw.

In the co-pending application of Justin M. Schmit, Ser. No. 32,933,filed Apr. 29, 1970, entitled STANDABLE FLEXI- BLE .CONTAINER WITH STRAWAND METHOD OF MANUFACTURING SAME, assigned to the same assignee as thepresent invention, the construction and use of a compartmented containerhaving a straw extending between compartments is disclosed. One aspectof this invention is the arrangement and use of a fold complex in thestraw which serves to shorten the straw and facilitate its properpositioning within one of the container compartments, as well asdefining a seal against the passage of liquid through the straw, untilthe straw is unfolded. The present invention is specifically concernedwith a machine for performing a fold sequence on a drinking straw toestablish this fold complex.

SUMMARY OF THE INVENTION A primary object of the invention is to providea simple machine for forming multiple folds in a conventionalpolyethylene plastic drinking straw to temporarily alter the strawsconfiguration and shorten it while establishing a seal at the foldsagainst the passage of liquids between container compartments. Anotherobject is to provide a machine which performs a straw folding operationof the aforedescribed nature with a minimum of operations, in thesimplest and most expeditious manner.

The foregoing and other objects are realized in accord with the presentinvention by providing a straw folding machine including a verticallydisposed frame having a straw bending chuck mounted for rotation about avertical axis. A straw bending anvil is also mounted on the frame inimmediately adjacent relationship with the rotatable chuck. A retainingarm arrangement positions a straw in vertical relationship against theanvil, with the straw already positioned in the plastic container asillustrated in the aforementioned co-pending application entitledSTANDABLE FLEXIBLE CONTAINER WITH STRAW AND METHOD OF MANUFACTURINGSAME. The liquid receiving compartment of the container may be empty orit may have been previously filled.

The anvil includes a first linear anvil surface which extendstransversely of the axis of the upright straw and is inclined at anangle of approximately 45 to the axis. Initial rotation of the chuckbends the straw over this anvil surface, whereby the straw is creasedalong an inclined crease line L and folded on this crease L until theupper section of the straw has been folded into a position perpendicularto the upright lower section of the straw. At this point, the chuck hasmade one rotation through 360.

The anvil includes a second linear anvil surface which extends parallelto the axis of the upright lower straw section and immediately adjacentto one of its edges. Continued rotation of the chuck folds the strawabout this second anvil surface and a second crease line L correspondingto the aforementioned vertical edge of the lower straw section. Foldingof the top section of the straw about the second crease continues underthe influence of the rotating chuck until the straw segment has beenfolded through an additional 180 (the chuck has rotated through 540),thus completing a 360 folding of the straw top section about its ownaxis through two folds at the first crease L, and the second crease L Acam arrangement on the chuck is effective, after this 540 of rotation ofthe chuck to actuate an anvil release mechanism, causing the anvil to bepivoted downwardly and out of engagement with the folded straw. Thefolded straw, with its container into which the lower straw sectionextends, is then moved to the next station where container flap guidespick up side flaps of the partially completed container about the foldedstraw and position them for ultimate sealing into a straw containercompartment. The chuck rotates through an additional to complete 720 ofrotation and one full cycle of operation of the machine.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevational view ofa straw folding machine embodying features of the invention, with astraw in its container positioned for folding;

FIG. 2 is a view similar to FIG. 1, with parts removed, showing themachine with its straw folding chuck rotated through 180 of a 720folding cycle;

FIG. 3 is an enlarged end view of a cam operator and its relation to astraw anvil release mechanism with the chuck positioned as illustratedin FIG. 2;

FIG. 4 is an enlarged view of a portion of the cam operatorconstruction;

FIG. 5 is an enlarged view of another portion of the cam operatorconstruction;

FIG. 6 is a view similar to FIG. 2 showing the straw folding chuck after360 of rotation in the 720 folding cycle;

FIG. 7 is an enlarged view of the cam operator as positioned when therotating chuck approaches (from the position shown in FIG. 6) its 540position in the 720 folding cycle;

FIG. 8 is a view similar to FIG. 6 showing the straw folding chuck inits 540 position of the 720 folding cycle; and

FIG. 9 is a view of the cam operator taken along line 9-9 of FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,and particularly to FIG. I, a straw folding machine embodying featuresof the present invention is illustrated generally at 10. The machine10'includes a vertically disposed frame 11 which includes a base member12, a vertical post 13 extending upwardly from the base member, and amounting bracket 14 secured to the upper end of the post 13.

The bracket 14 includes a cantilevered arm 20 extending outwardly fromthe post 13 and a body counterweight 21. The body 21 is clamped to thevertical post 13 with an adjusting screw 22, facilitating verticaladjustment of the bracket 14 on the post 13, for reasons hereinafterdiscussed in detail.

Having described the machine 10 to this extent, it is necessary beforecontinuing a description of the construction and operation to describethe positioning of the container C and the straw S. The construction ofthe container C and the arrangement of the straw S in the container isdescribed in detail in the aforementioned co-pending applicationentitled STANDABLE FLEXIBLE CONTAINER WITH STRAW AND METHOD OFMANUFACTURING SAME.

The container C, with its lower compartment filled with liquid (in theillustrated example) and the straw S extending vertically therefrom, isseated on the base 12 by suitable mechanical means. In this position,the straw protrudes from the lower compartment of the container C andextends into immediately adjacent relationship with a chuck assembly 30mounted on a vertical pin 31 affixed to the outer end of the arm 20 forrotation about the axis of the pin. In the illustration of FIG. 1, itwill be seen that the straw extends upwardly in front of the chuckassembly in normal, unactuated relationship of the machine 10.

In this relationship, the straw S is positioned against the anvil arm 35which is pivotally mounted for vertical movement on a pin 36 on theframe post 13. In a manner hereinafter described, the chuck assembly 30is effective to fold the straw S on the anvil 35 to form a fold complexwhich shortens the straw and defines a liquid tight seal in the straw,preventing the efflux of liquid from the lower compartment of thecontainer C as long as the straw is folded.

The anvil arm 35 is formed of metal strip and includes an anvil section37 formed at its outermost end. It is the anvil section 37 against whichthe straw S is placed. The anvil section 37 includes a first linearanvil surface 40 which extends transversely of the axis of the uprightstraw and is inclined at an angle of approximately 45 to the axis. Theanvil section 37 includes a second linear anvil surface 41 which extendsparallel to the axis of the upright straw S and immediately adjacent toone edge of this straw, as viewed in front elevation in FIG. 1.

The anvil arm 35 is normally biased into horizontal relationship whereinthe anvil surfaces 40 and 41 are arranged in the manner hereinbeforedescribed, by an anvil arm coil spring 45 disposed between an extension46 of the anvil arm 35 and a mounting bracket 47 adjacent the base 12 onthe frame 11 The anvil arm 35 is stopped in this horizontal positionagainst further movement under the influence of the spring 45 by a stopscrew 49 which is adapted to engage the upright post 13 with the anvilarm in this position.

The chuck assembly 30 includes a mounting block 55 from which a strawbending head 56 depends. The straw S is, before actuation of the machinein a folding cycle, disposed immediately adjacent the front face 60 ofthe head 56. The upper end of the straw is actually positioned in frontand slightly to one side of a generally conical groove 61 formed in theface 60 of the head 56 and converging upwardly from a widened area atthe base 62 of the head 56 to a narrower area at the top 63 of the head56. At the base 62 of the head 56, the groove 61 is sufficiently deep toextend into the back face 66 of the head 56, thus creating a generallyelliptical cut-out 67 in the back face 66, extending upwardly from thebase 62 of the head.

The groove 61, adjacent which the upper end of the straw S is disposedprior to beginning of the straw folding operation by the machine 10, isoffset slightly in the direction of its axis pin 31 from the axis of thestraw in this relationship. At the same time, the axis of the straw Sand the groove 61 are offset from the axis of rotation of the chuckassembly 30 in the direction of the post 13. The significance of thisoffset relationship will be explained in the description of theoperation of the machine 10. i

It is the rotation of the straw bending head 56 about the axis of itsmounting pin 31 which is effective to fold the straw S about the anvilsurfaces 40 and 41 hereinbefore described. One folding cycle of themachine is effected by rotation of the chuck assembly 30 through 720, ortwo complete 360 halfcycles, returning to its normal or startingposition, as illustrated in FIG. 1.

During the first 360 half-cycle of the folding operation performed bythe rotating chuck head 56, after approximately 180 of rotation, as seenin Fig. 2, the upper end of the straw S has just been engaged by thehead 56 at the outermost extremity 70 of one side of the groove 61.Continued rotation of the head 56 bends the straw S over the anvilsurface 40, creasing it along an inclined crease line L and folding theupper section of the straw on this line L until the head has rotatedthrough one full half-cycle or 360, as seen in FIG. 6. At this point,the upper section of the straw, above the crease line L,, has beenfolded into a position perpendicular to the upright lower section of thestraw below the crease line L In effecting this folding of the uppersection of the straw S about the crease line L,, from initial contact ofthe groove area 70 with the straw through 360 of rotation of the head56, the upper section of the straw S rides in the groove 61 and isguided into the aforedescribed relationship perpendicular to the lowerstraw section.

As the straw S approaches this perpendicular (horizontal) relationship,wherein it extends generally parallel to the anvil arm 35, it movesdownwardly out of the groove 61 until it actually slips underneath thebase 62 of the head 56, as seen in FIG. 6. At this point, the uppersection of the straw S comes into engagement with the straw bendingguide pin 75 which depends from the base 62 of the head 56 opposite theaxis of rotation of the chuck assembly from the groove 61. An enlargedhead 76 is formed on the lower end of the pin 75 to prevent the strawfrom slipping off.

With the initially folded upper section of the straw S biased by its ownresiliency against the guide pin 75, continued rotasum tion of the chuckassembly 30 folds the upper section of the straw about the second anvilsurface 41, forming a vertical crease line L until the straw section hasbeen folded through an additional 180 (the chuck assembly 30 has rotatedthrough 540), as seen in FIG. 8, thus completing a 360 folding of thestraw top section about its own axis through two folds at the firstcrease L and the second crease L When the chuck assembly has rotatedthrough 540 of the 720 straw folding cycle, a cam unit 80 on the chuckassembly 30 is effective to engage and depress a straw release arm 81mounted for pivotal movement at 82 on the vertical post 13 of themachine frame 1 1. The cam unit 80 engages the inner end 85 of therelease arm 81, forcing it downwardly and, accordingly, forcing theouter end 86 of the cam arm upwardly. The outer end 86 of the cam arm 81is connected, by suitable linkage 87, to the extension 46 of the anvilarm 35. Accordingly, it pivots the anvil arm 35 on its mounting pin 36,against the bias of the spring 45, forcing the anvil section 37 of theanvil arm downwardly and out of engagement with the straw fold complexformed at thecrease lines L and L The construction and operation of thecam unit 80 in its engagement with and depression of the release arm 81is best understood by reference to FIGS. 3-9. The cam unit 80 includesan elongated cam 90 rotatably mounted on a pin 91 extendingperpendicular to the axis of rotation of the chuck assembly 30 of thechuck head 56. Secured to the end of the pin 91 on a mounting disc 92 isa conventional split lock washer 93. Secured to the inner surface of thecam arm 90 is a cooperating bearing disc 94. Dimples are formed at 90intervals around the disc 94 so that in rotation of the arm 90 on theshaft 91 they seat in the washer gap 93a, engage the partially outwardlysprung end of the washer, and act as a stop in positioning the cam arm90 and preventing its otherwise free rotation on the shaft 91.

The cam arm 90 is preset in the position illustrated in FIG. 4 at theoutset of an operational folding cycle of the machine 10. In thisposition, it will be noted that the arm 90 is horizontally disposed. Adimple on the disc 94 in the lock washer gap 930 lightly holds the camarm 90 in this position.

When the chuck assembly 30 has rotated through the first of itsrotational folding cycle, as it begins to fold the straw about thecrease line L a depending inclined cam face 97 on the cam arm 90 engagesthe inner end 85 of the release arm 81. Since the cam arm 90 is onlylightly held in its horizontal relationship by the seating of the dimple95 in the lock washer slot 93a, this engagement causes the cam arm 90 torotate approximately 30 about the axis of its mounting pin 91, asillustrated in FIG. 3. The cam arm 90 is retained in this position bythe friction between the dimples 95 on the disc 94 and the lock washer93 until the chuck assembly has rotated through an additional 360bringing the straw to its fully folded relationship and the cam assembly80 back into engagement with the release arm 81.

At this point, as best seen in FIG. 7, the arcuate cam surface 98engages the release arm free end 85. Further rotation of the chuckassembly 30 effects a depression of the release arm 81 and a continuedrotation of the cam arm 90 into the relationship illustrated in FIG. 9.At this point, the release arm 81 has pivoted the anvil arm 35downwardly to withdraw the anvil section 37 from engagement with thefolded straw S.

The straw S is now completely folded according to the invention. At thispoint, the container C is withdrawn horizontally from the machine 10,between arcuate container flap guides 99, extending onto opposite sidesof the container immediately below the straw fold, from the cantileveredarm 20. By drawing the container C outwardly between these arms 99,flaps of the container lying down over the guides during the foldingoperation are forced upwardly alongside the folded upper section of thestraw S into position for scaling to form an upper container compartmentwhich encloses the folded straw.

Continued rotation of the chuck assembly 30 through its final 180 of the720 folding cycle further rotates the cam arm about its mounting pinaxis 91 until it finally disengages with the release arm surface 85.Although the cam arm may not return to a precisely horizontalrelationship at this point, it is unnecessary that it do so, since inthe next cycle of operation its initial engagement of the cam face 97with the release arm free end 85 will still serve to position the arm 90as illustrated in FIG. 3.

Rotation of the chuck assembly 30 is effected by a conventional electricmotor 100 and belt 101 to a pulley 102 on the shaft 31. Suitable timingdevices and circuitry sequence the rotation in the aforedescribedmanner.

The head 14 is vertically adjustable, as hereinbefore pointed out.Variations in straw length can thus be accommodated easily.

While the embodiment described herein is at present considered to bepreferred, it is understood that various modifications and improvementsmay be made therein.

What is desired to be claimed and secured by Letters Patent of theUnited states is:

l. A machine for folding a straw to temporarily change the configurationand dimensions of the straw and form a liquidtight seal in the straw,comprising:

a. anvil means b. means for holding an unfolded straw with itscylindrical side wall disposed immediately adjacent said anvil means,

. chuck means rotatable on an axis parallel to the axis of the unfoldedstraw,

. straw directing means on said chuck means,

. rotation of said chuck means causing said straw directing means tofold an upper section of said straw on said anvil means intoperpendicular relationship with a lower section of the straw andestablish a liquid tight seal between said upper and lower strawsections.

2. The straw folding machine of claim 1 further characterized in that:

a. a first linear anvil surface formed on said anvil means and extendingtransversely to the axis of the unfolded straw and at an oblique anglethereto,

b. a second linear anvil surface on said anvil means and extendingsubstantially parallel to the axis of the unfolded straw,

. rotation of said chuck means causing said upper section of said strawto fold on a first crease line over said first anvil surface and on asecond crease line over said second anvil surface.

3. The straw folding machine of claim 2 further characterized in that:

a. said chuck means rotates from a starting position through a 720 cycleof rotation to a finish position in folding the upper section of thestraw about said first linear anvil surface and said second linear anvilsurface into perpendicular relationship with the lower section of thestraw.

4. The straw folding machine of claim 3 further characterized in that:

a. rotation of said chuck means from its starting position through 360of its 720 cycle being effective to fold the straw over said firstlinear anvil surface on said first crease line into perpendicularrelationship with the lower straw section,

b. rotation of said chuck means from the 360 position in its foldingcycle to its 540 position in its folding cycle being effective to foldthe upper straw section over said second linear anvil surface on saidsecond crease line to complete the folding of the straw andestablishment of said liquidtight seal while maintaining a perpendicularrelationship between the upper straw section and the lower strawsection.

5. The straw folding machine of claim 4 further characterized in that:

a. said chuck means includes a chuck head,

b. said straw directing means including a groove formed in one face ofsaid chuck head in generally parallel relationship with the axis ofrotation of said chuck means and the axis of the unfolded straw,

c. said groove being effective to engage the straw as the chuck headrotates through the first 360 of the 720 straw bending cycle of theanvil means to fold the upper straw section over said first linear anvilsurface into perpendicular relationship with the lower straw section.

6. The straw folding machine of claim 5 further characterized in that:

a. said straw directing means further includes a straw directing pinmeans extending from the base of said chuck head in generally parallelrelationship with the axis of rotation of the anvil means and the axisof the unfolded straw,

b. said pin means engaging the upper section of the straw afterapproximately said initial 360 rotation of the chuck means and directingsaid straw to fold around said second linear anvil surface on saidsecond crease line as said chuck head rotates through said 360 to 540portion of its straw folding cycle.

7. The straw folding machine of claim 6 further characterized in that:

a. said anvil means is movable from an operative position for engagementby the straw and folding of the upper straw section over said first andsecond linear anvil surfaces, and an inoperative position,

b. actuator means on said chuck means for causing said anvil means tomove from its operative position to its inoperative position when thechuck means has rotated through 540 of its 720 straw folding cycle andthe upper straw section has been folded on said first and second creaselines into perpendicular relationship with the lower section of thestraw.

8. The straw folding machine of claim 7 further characterized in that:

a. said actuator means comprises a cam mounted on said chuck means,

b. an anvil arm connected to said anvil,

c. said cam adapted to engage said anvil arm and cause it to move saidanvil from its operative position to its inoperative position as therotating chuck means passes the 540 position in its 720 cycle ofrotation.

9. The straw folding machine of claim 8 further characterized by andincluding:

a. resilient means normally urging said anvil means from its inoperativeposition to its operative position.

10. The straw folding machine of claim 9 further characterized in that:

a. said cam is rotatable on said chuck means about an axis extendinggenerally perpendicular to the axis of rotation of the chuck means,

b. a first cam surface on said cam for engaging said arm and cockingsaid cam as it passes through its 360 position in the 720 cycle ofrotation of the chuck means,

0. a second cam surface on said cam for engaging said actuator arm onlywith the cam in its cocked position as the rotating chuck passes throughits 540 position in its 720 cycle of rotation.

11. A machine for folding a straw to temporarily change theconfiguration and dimensions of the straw and form a liquidtight seal inthe straw, comprising:

a. means for supporting a straw,

b. means for folding an upper section of said straw in a predetermineddirection about a first crease line in said straw to bring said uppersection into a first position generally perpendicular to the lowersection of said straw, and

c. means for further folding said upper section of said straw insubstantially the same direction about a second crease line in saidstraw adjacent said first crease line into a position extending insubstantially the opposite direction from the first position of saidupper straw section.

12. The straw folding machine of claim 11 further characterized by andincluding:

a. means for forming said first crease line in said straw at an obliqueangle to the axis of the unfolded straw.

13. A method of folding a straw to temporarily change the said firstcrease line and extending generally parallel to configuration anddimensions of the straw and form a liquid the axis of the other strawsection, and tight seal in the straw, comprising the steps of: d.folding the upper section of said straw about said second a. creasingthe straw intermediate its ends along a fir t crease line until saidupper section extends in a direction crease line extending diagonal tothe axis of the straw, Substantially pp that in which it resides beinginitially folded about said first crease line into a position generallyperpendicular to the other end section of said straw.

b. folding one end section of the straw on said first crease line intogenerally perpendicular relationship to the other end section of thestraw,

c. creasing the straw along a second crease line adjacent

1. A machine for folding a straw to temporarily change the configurationand dimensions of the straw and form a liquid-tight seal in the straw,comprising: a. anvil means b. means for holding an unfolded straw withits cylindrical side wall disposed immediately adjacent said anvilmeans, c. chuck means rotatable on an axis parallel to the axis of theunfolded straw, d. straw directing means on said chuck means, e.rotation of said chuck means causing said straw directing means to foldan upper section of said straw on said anvil means into perpendicularrelationship with a lower section of thE straw and establish a liquidtight seal between said upper and lower straw sections.
 2. The strawfolding machine of claim 1 further characterized in that: a. a firstlinear anvil surface formed on said anvil means and extendingtransversely to the axis of the unfolded straw and at an oblique anglethereto, b. a second linear anvil surface on said anvil means andextending substantially parallel to the axis of the unfolded straw, c.rotation of said chuck means causing said upper section of said straw tofold on a first crease line over said first anvil surface and on asecond crease line over said second anvil surface.
 3. The straw foldingmachine of claim 2 further characterized in that: a. said chuck meansrotates from a starting position through a 720* cycle of rotation to afinish position in folding the upper section of the straw about saidfirst linear anvil surface and said second linear anvil surface intoperpendicular relationship with the lower section of the straw.
 4. Thestraw folding machine of claim 3 further characterized in that: a.rotation of said chuck means from its starting position through 360* ofits 720* cycle being effective to fold the straw over said first linearanvil surface on said first crease line into perpendicular relationshipwith the lower straw section, b. rotation of said chuck means from the360* position in its folding cycle to its 540* position in its foldingcycle being effective to fold the upper straw section over said secondlinear anvil surface on said second crease line to complete the foldingof the straw and establishment of said liquid-tight seal whilemaintaining a perpendicular relationship between the upper straw sectionand the lower straw section.
 5. The straw folding machine of claim 4further characterized in that: a. said chuck means includes a chuckhead, b. said straw directing means including a groove formed in oneface of said chuck head in generally parallel relationship with the axisof rotation of said chuck means and the axis of the unfolded straw, c.said groove being effective to engage the straw as the chuck headrotates through the first 360* of the 720* straw bending cycle of theanvil means to fold the upper straw section over said first linear anvilsurface into perpendicular relationship with the lower straw section. 6.The straw folding machine of claim 5 further characterized in that: a.said straw directing means further includes a straw directing pin meansextending from the base of said chuck head in generally parallelrelationship with the axis of rotation of the anvil means and the axisof the unfolded straw, b. said pin means engaging the upper section ofthe straw after approximately said initial 360* rotation of the chuckmeans and directing said straw to fold around said second linear anvilsurface on said second crease line as said chuck head rotates throughsaid 360* to 540* portion of its straw folding cycle.
 7. The strawfolding machine of claim 6 further characterized in that: a. said anvilmeans is movable from an operative position for engagement by the strawand folding of the upper straw section over said first and second linearanvil surfaces, and an inoperative position, b. actuator means on saidchuck means for causing said anvil means to move from its operativeposition to its inoperative position when the chuck means has rotatedthrough 540* of its 720* straw folding cycle and the upper straw sectionhas been folded on said first and second crease lines into perpendicularrelationship with the lower section of the straw.
 8. The straw foldingmachine of claim 7 further characterized in that: a. said actuator meanscomprises a cam mounted on said chuck means, b. an anvil arm connectedto said anvil, c. said cam adapted to engage said Anvil arm and cause itto move said anvil from its operative position to its inoperativeposition as the rotating chuck means passes the 540* position in its720* cycle of rotation.
 9. The straw folding machine of claim 8 furthercharacterized by and including: a. resilient means normally urging saidanvil means from its inoperative position to its operative position. 10.The straw folding machine of claim 9 further characterized in that: a.said cam is rotatable on said chuck means about an axis extendinggenerally perpendicular to the axis of rotation of the chuck means, b. afirst cam surface on said cam for engaging said arm and cocking said camas it passes through its 360* position in the 720* cycle of rotation ofthe chuck means, c. a second cam surface on said cam for engaging saidactuator arm only with the cam in its cocked position as the rotatingchuck passes through its 540* position in its 720* cycle of rotation.11. A machine for folding a straw to temporarily change theconfiguration and dimensions of the straw and form a liquid-tight sealin the straw, comprising: a. means for supporting a straw, b. means forfolding an upper section of said straw in a predetermined directionabout a first crease line in said straw to bring said upper section intoa first position generally perpendicular to the lower section of saidstraw, and c. means for further folding said upper section of said strawin substantially the same direction about a second crease line in saidstraw adjacent said first crease line into a position extending insubstantially the opposite direction from the first position of saidupper straw section.
 12. The straw folding machine of claim 11 furthercharacterized by and including: a. means for forming said first creaseline in said straw at an oblique angle to the axis of the unfoldedstraw.
 13. A method of folding a straw to temporarily change theconfiguration and dimensions of the straw and form a liquid tight sealin the straw, comprising the steps of: a. creasing the strawintermediate its ends along a first crease line extending diagonal tothe axis of the straw, b. folding one end section of the straw on saidfirst crease line into generally perpendicular relationship to the otherend section of the straw, c. creasing the straw along a second creaseline adjacent said first crease line and extending generally parallel tothe axis of the other straw section, and d. folding the upper section ofsaid straw about said second crease line until said upper sectionextends in a direction substantially opposite that in which it residesafter being initially folded about said first crease line into aposition generally perpendicular to the other end section of said straw.